#![allow(dead_code, deprecated, unused_variables, unused_mut)]
#![feature(bigint_helper_methods)]
fn scalar_mul_eq(little_endian_digits: &mut Vec<u16>, multiplicand: u16) {
    let mut carry = 0;
    for d in little_endian_digits.iter_mut() {
        (*d, carry) = d.carrying_mul(multiplicand, carry);
    }
    if carry != 0 {
        little_endian_digits.push(carry);
    }
}
fn main() {
    let mut v = vec![10, 20];
    scalar_mul_eq(&mut v, 3);
    assert_eq!(v, [30, 60]);
    assert_eq!(0x87654321_u64 * 0xFEED, 0x86D3D159E38D);
    let mut v = vec![0x4321, 0x8765];
    scalar_mul_eq(&mut v, 0xFEED);
    assert_eq!(v, [0xE38D, 0xD159, 0x86D3]);
}